Art of preparing nitrated aminobenzol arsinic acid.



Lonunz ACH, orivmunnnnvr, AND ALBERT ItorHMANn AND HANS HATZIG, or YHEIDELBERG, GERMANY, ASSIGNORS T FARBWERKE VORM. MEISTER LUCIUS & BRUENING, or H6GHST-QN-THE-MAIN,, GERMANY, A FIRM.

.AIt'I. OF PREPARING NITRATED AMINOBENZOL ARSINIC ACID.

No'Di'awing. Application filed December 20, 1913.

To all whom it may concern:

Be it known that we, Lonnxz A011, AL- BERT Ro'ri-IMANN, and HANS HATZIG, citizens of the German Empire, the said AcH residing, at Mannheim, Baden, and the said ROTHMANN- and HATZIG at Heidelberg, Baden, Germany, have invented certain new and useful Improvements in the Art of Preparing Nitrated Aminobenzol Arsinic Acid, and that we do hereby,

declare the following to be a full, clear,

and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the ondary amins, but compounds of the type of" same. a

Mononitro-aminobenzenearsinic acids and .dinitro-aminobenzenearsinic acids, which are of considerable importance in the manufacture of valuable medicinal arsenic-compounds, have heretofore been made by the nitration of aminobenzene arsinic acids or of their N-acidyl derivatives, such processes having been described in German Patents Nos. 231969 and 232879, and also in Bem'ohte der Deutschen Uhemz'sohen Gesellschaft, vol.

upon meta meta dinitroparachlorobenzene arsinic acid with a compound comprising the amino group, under which term we nclude not only ammonla and primary and secamino-acetic acid, of benzene sulfonamid, or of piperidin, as well. In other words, we may use as such a reagent a compound having the general formula HNR R' wherein each of the symbols R, and R denotes a monovalent' radical, the term radical including an element as well as a group of elements. In this way We have succeeded in introducing into the benzene-nucleus the monovalent residue where R, designates a monovalent radical or element such as alkyl or hydrogen and It, also designates a monovalent radical Specification of Letters Patent.

' from Patented Dec. v, 1915. Serial No. 807,908. 7

or element, such as hydrogen,

CH .COOH, or SO Aryl.

In the case of preparing the dinitro aminobenzenearsinic acid one may start not only I 3.5-d1n1tro-1-chl0robenzene-1-arsinic acid directly but also from the mononitrochlorin-comp'ound which may be further nitrated to produce a 4t-chloro-3.5-dinitrobenzene-1- arsinlc acid, the chlorin-atom being then replaced, as above, or we may proceed from 1- c'hloro-3-nitrobenzene-1-arsinic acid, replacing the chlorin in this acid and introducing lnto the amino compound so formed'a second nitro group.

In order to'fully disclose our invention we will now recite 1n detall a number of examples embodying what we consider the preferable manner of carrying the same into I effect- Example 1: 281 grams of t-chloro-3-nitrobenzene-l-arsinic acid, (described in Ger.-

man 'Patent No. 245536) are heated with 500 cubic centimeters of a 15 per cent. aqueous solution of ammonia to 120 in an autoclave and maintained at this temperature for two hours. A 'red clear solution is thus obtained and from this solution t-amino-3-nitrobenzene-l-arsinic. acid is separated by adding concentrated hydrochloric acid thereto. This compound possesses all the properties of #l-amin0-3-nitrobenzene-1-arsinic acid enumerated in Bem'ohte (ler Deutschen Ohemiwhen Gesellschaft, vol. 44.- (1911), page 3095. In order to obtain .the dinitro compound from the 1-amino-B-nitrobenzene arsinic acid, 131 grams of the same are dissolved in 300 grams of monohydrate of sulfuric acid at from 5 to 10 Centigrade, whereupon 150 cubic centimeters of a mixture of nitric and sulfuric acids known as nitrating acid are added to the whole at a temperature of. from 0 to 59 6., while stirring. The temperature is then allowed to gradually rise to 15 0., during an interval of 2 hours, whereupon the whole is poured onto ice. Thereby 4-amino- 3.5-dinitrobenzenearsinic acid is obtained and may be in Berichte er Deutschen Okemz'eahen G eseZZ- sohaft, vol. 4511912) p. 56.

' Example 2: 281 grams of 1-chloro-3-nitrobenzene-l-arsinic acid are dissolved in 680 cubic centimeters of pentanormal aqueous so- 10 alkyl, 1

urified in the manner set forth almost insoluble in water and dilute mineral acids, and 'soluble with difficulty in cold alcohol. It is readily-soluble in 'alkalis, sodium acetate solution'and hot alcohol. If this mononitro compound is exposed to the action of concentrated nitric acid, not only a further nitro group becomes bound to the benzene-nucleus, but a further nitro group combines with the methylamino group, a

nitramin being formed. Accordingly by heating 1&8 grams of this new compound, the eldnethylamino-3-nitrobenzene-l-arsinic acid, together with 550 grams of fuming nitrio acid on the water bath for 2 hours the compound described in Letters Patent of the United States No. 1075279 to 'Ach & Rothmann, dated Oct. 7, 1913, and designated as 3. 5- dinitro -4-met-hyl-nitraminobenzene-l-arsinic acid, is, obtained.

Example 3: 163 grams of 4 .-chloro-3-nitrobenzene-l-arsinic acid are subjected to energetic nitration in sulfuric acid solution. It

is thereby converted into al-chloro-do-nitrd jbenzene-l-arsinic acid, taking the form of ether.

and sodium-acetate solution.

- white crystals which are readily soluble in alcohol, in hot water and in strong hydrochloric acid and ,which decrepit-ate or pull away on heating. The entire quantity of this so obtained new compound is then heated in 500 grams ethyl alcohol and then mixed wit-11,225 cubic centimeters of a 15 per cent solution of methylamin in alcohol and moderately heated on the water bath for some time (about three hours).' Thereupon the major portion of the alcohol is distilled oil in mono and the residue is acidulated with hydrochloric acid. Thereby the new body, it: methylamino 3.5-dinitrobenzene-L arsinic acid is thrown out as a yellow crystalline powder. This new compoundis readily soluble in hot alcohol, glacial acetic acid In alkalis it dissolves forming a-reddish-brown solution. It is insoluble in mineral acids, acetone and On heating, it decomposes the decomposition being attended by decrepitation or pulling away.

Example 4: 141' grams of 4-chloro-3-nitrobenzene-l-arsinic acid are dissolved in 500 cubic centimeters of hot alcohol, the solution bein mixed with150 grams of 33 per cent. alcoholic solution of dimethylamin and heated for some time (about three hours) on 'same.

. autocla re for the water bath. The alcohol is then distilled oil in cacao. On cooling the new compound, l dimethylamino 8 -nitrobenzene l-arsenic acid is obtained in the form of yellow acicu- .lar crystals, which are recrystallized from cubic centimeters of pentanormal sodium hydrate solution, whereupon grams of amino-acetic acid are added to the whole. When solution has taken place, the same is heated to 50 (3., in a reflux cooler and maintained at this temperature for 30 hours. From the resultant red solution the new compound, i-glycin-Zi-nitrobenzene-1-arsinic acid, is then precipitated by means of dilute sulfuric acid. This new acid is yellow in color, it is insoluble in acetone, in ether and in glacial acetic acid, but soluble in hot alcohol and in hot water. In alkali it dissolves with a yellowish-red color. On heating, it decomposes with mild decrepitation.

Example 6: 326 grams of 4l-chlor0-3.5-

dinitrobenzene-l-arsinic acid are dissolved in 2000 cubic centimeters of normal sodium lye and 2000 cubic centimeters of ice-water, whereupon 80 grams of glycocoll or aminoacetic acid in 1060 cubic centimeters of normal sodium lye are added to the solution while stirring .or otherwise agitating the whereby the new compound, lglycin-3.5- dinitrobenzene arsinic acid is precipitated as a greenish-yellow.powder. On heating the compound pulls away or decrepitates. It dissolves in alkali, the solution being red in color.- "It is insoluble in ether, but soluble in hot water, in alcohol, in glacial acetic acid and in acetone.

Example? 281 grains of 4-cliloro3-nitro beuzene-l-arsinic acid are dissolved in 620 cubic centimeters of pentanormal sodium lye together with 168 grams of benzenesulfonamid and maintained at 120 C. in an 2 hours and then at 150 C; for 9 hours. The product of this reaction is precipitated with a dilute acid and the preci itate is then extracted with ether for the removal of the benzene-sulfonamid ac companying the same. The residue, that is to say, the undissolved 4c-benzenesulfon amido-3-nitrobenzene l arsinic acid is thus obtained as light-brown compound, which is readilv soluble in alkali as a yellow solution. It readily dissolves in water or in alcohol under the imfluenceof heat, less readily in acetone. It is insoluble in ether. On heating it decomposes. I Example. 8: 326 grams of 4-'chloro-3 .5- dinitrobenzene-l-arsinic acid together with The whole is then allowedto stand for 24: hours at a temperature of 20 C.,

1 other radical.

-Ze'n 168 grams of benzenesulfonamid are added to 620 cubiccentimeters of pentanormal sodium lye and maintained at a temperature of 120 C. in an autoclave ,for two hours, and then at 150 for 6 hours. The reaction product" is then recipitated with a dilute acid and extracteclwith ether, as in Example 7. Thereby the new compound, 4-benzene- -sulfonamido 3.5 dinitrobenzene 1 arsinic "arsinic acid wherever used in the clai one or both hydrogen atoms in the metaposition are replaced by the nitro group.

Claims:

1. The process of making meta-nitropara-amino-benzene consists in reacting on meta-nitro-parachloro-benzene arsinic acids with a compound of the formula HNR,R wherein .each of the symbols R and R denotes a monovalent radical.

'2. The process of making meta-nitropara-amino-benzene arsinic acids, which consists in reacting on meta-nitro-pararchloro-benzene arsinic acids with an amino compound.

3. The process of making 3.5-dinitro-4- amino-benzene arsinic acid which consists in reacting on 3.5dinitro-4-chloro-benzene arsinic acid with a compound of the formula PINE- R wherein each of the symbols R andR. denotes a monovalent radical.

.4}. The process of making 3.5-dinitro-4- amino-benzene arsinlc acids, whlch consists in reacting on 3.5-d1n1tro-4-chloro-benzene 'arsinic acid with an amino compound.

5. The process of making a meta-nitro- The term meta-nitro-ben-- ms designates nitro compounds in which arsinic acids, which para-methylamino benzene arsinic acid compound, which consists in reactmg on a metanitro-para chloro-benzene arsmlc acid compound with methylamin.

6. The process of making 3.5-dinitro-4- methylamino-be-nzene arsinic acid, which consists in reacting on 3.5-dinitro-4-chlorobenzene arsinic acid with methylamin.

7. As a new class of chemical compounds the 3.5-dinitro-l-amino-benzene arsinic acids of the general formula NHR (where R designates any monovalent radical) which are solid crystalline substances of yellow or brownish color, insoluble at the ordinary temperature in water and most organic solvents, insoluble in dilute mineral acids, soluble in alkalis and sodium acetate solution and slightly soluble in hot alcohol and acetone. decomposing on heatin 8. As a new composition of matter the 3.5- dinitro-i-methylamino benzene arsinic acid possessing the formula AsO(0H)= which is readily soluble in hot alcohol, glacial acetic acid and sodium acetate solution,

insoluble in mineral acids, acetone and'ether, dissolving in alkalis, forming a reddishbrown solution, decomposing on heating by decrepitation.

In testimony whereof we hereunto aflix our signatures in the presence of two wit- LORENZ ACH. ALBERT ROTHMANN. HANS HATZIG.

, lVitnesses:

HERMANN DIETERICH, S. S. BERGER. 

